Suspending a Speaker: What is T in each cable

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The discussion centers on solving for tension (T) in a cable suspending a loudspeaker, with a focus on the angle calculation. The user initially calculated the angle using arcsin and derived T as approximately 84.28 N. However, they encountered an error with MasteringPhysics, which stemmed from misinterpreting degrees as radians. A clarification was provided that the sine function could be approached differently, avoiding the need for angle determination. The conversation emphasizes the importance of verifying units and calculations in physics problems.
pemby
1. The problem statement, all variables, and given/known data
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Homework Equations


Assuming standard coordinates, Net forces in the x plane are 0, by
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The Attempt at a Solution



I have worked out that

\arcsin { \left( \frac { 1.4 }{ 3.1 } \right) } =\quad 26.8{ 5 }°\\ loud\quad speaker\quad =\quad wg\quad =\quad 166.77\quad N\\ 2T\sin { \left( 26.8{ 5 }° \right) \quad =\quad 166.77 } N\\ T\quad =\quad 84.2824

Masteringphysics returning with an incorrect solution response and is giving me this piece of information.

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I do not understand what this error implies.
I have tried;

\\ T\sin { \left( 26.8{ 5 }° \right) \quad =\quad 166.77 } N\\ \\ \\ T\sin { \left( \frac { 1 }{ 2 } 26.8{ 5 }° \right) \quad =\quad 166.77 } N\\ \\ T2\sin { \left( 26.8{ 5 }° \right) \quad =\quad \frac { 166.77\quad N }{ 2 } }
 

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Radians v. degrees.
 
Sorry, can you expand a bit more? I understand the difference but not in the context of this question.
 
pemby said:
sin(26.85°)
What value did you get for that?
 
haruspex said:
What value did you get for that?
0.438371146789077417452734540658265739062755719988552114431
 
pemby said:
0.438371146789077417452734540658265739062755719988552114431
Then I do not see how you could have got that final answer. You had
pemby said:
2Tsin(26.85°)=166.77N
Maybe you halved twice?
 
Thanks. it was reading my degrees as radians. I tricked my self by not double checking!
 
pemby said:
Thanks. it was reading my degrees as radians. I tricked my self by not double checking!
OK.

Btw, you can often avoid figuring out the angle. In the present case, you wanted sin(θ), which is h/l, so the accurate answer is 17g*3.1/(2*1.4).
 
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